Kubernetes

Commands: dob dks config, dob dks attach-node

This feature streamlines the automated provisioning and configuration of Kubernetes clusters (DKS - DOB Kubernetes Services) on cloud infrastructure.

Key Highlights:

1. DKS Configuration Command
   • Command: dob dks config --file-path <yaml-config>
   • Functionality:
     • Provisions and configures Kubernetes master and worker nodes using the provided YAML configuration.
     • Generates Kubernetes join tokens for worker nodes automatically.
     • Includes a retry mechanism for transient failures during node setup.
   • Error Handling:
     • Validates configuration files and handles missing or invalid files.
     • Provides detailed error messages for provisioning or Kubernetes setup failures.
2. Attach New Worker Nodes
   • Command: dob dks attach-node --file-path <yaml-config>
   • Functionality:
     • Attaches new worker nodes to an existing Kubernetes master node.
     • Uses the master node's join token for worker node setup.
   • Error Handling:
     • Ensures proper detection of the master node before attaching workers.
     • Provides clear error feedback for failures during the join process.
3. Default Tasks for Master Nodes
   • Disabling SELinux and enabling IP forwarding.
   • Installing and configuring Docker and Containerd.
   • Installing Kubernetes components (kubelet, kubeadm, kubectl) and initializing the master node.
   • Deploying Calico as the default network plugin.
4. Default Tasks for Worker Nodes
   • Disabling SELinux and enabling IP forwarding.
   • Installing Docker, Containerd, and Kubernetes components.
   • Automatically joining the worker nodes to the cluster using the join token.
5. Error Handling and Logging
   • Comprehensive error handling with retry logic for transient issues.
   • Real-time logging of task execution for better visibility and debugging.

Example YAML Configuration:

  master:
    name: k8s-master
    instance_type: t2.medium
    key_name: my-ssh-key
    security_group: my-security-group
  workers:
    name: k8s-worker
    instance_type: t2.small
    key_name: my-ssh-key
    security_group: my-security-group
    count: 3
      

Example Usage:

  dob dks config --file-path /path/to/config.yaml
  dob dks attach-node --file-path /path/to/new-workers-config.yaml